Businesses, governmental agencies, learning institutions, and other organizations typically operate computers that are interconnected by a network. Network users often store data on hard drives of network servers. Users also store data on their host computers.
Data stored on the network and/or host computers is typically backed-up periodically to create a copy of the data to prevent it from being lost due to mechanical failure or accidental deletion, for example, and/or to produce an archive of the data. Backup operations typically involve storing a copy of all or a portion of the data files on the network and/or host computers to a backup device such as a magnetic tape library having a plurality of magnetic tape drives.
Digital magnetic tape has long been used for data storage in computer systems. The low cost-per-bit stored, long-term retention capability, and portability of magnetic tape cartridges have made them invaluable for storing large quantities of data generated by businesses.
Tape cartridges are used by automated tape library devices. Tape libraries generally handle many tape cartridges to store very large amounts of data. The tape libraries hold the tape cartridges in predefined positions or media slots. When data is required from a particular tape cartridge, a host system communicates via a Small Computer System Interface (SCSI) bus or a Fibre Channel (FC) fabric, for example, with a controller of the tape library. The controller retrieves the particular tape cartridge from its media slot and places the tape cartridge in a tape drive. The host system may then read from or write to the tape cartridge via the tape drive. Also, the host system may query the controller to determine the number of tape cartridges, tape drives, and robotics mechanisms contained in the tape library to manage the tape library.
There are a number of manufacturers of tape libraries that back up and store large quantities of data to digital magnetic tape cartridges. For example, a StorageWorks brand of tape libraries are manufactured in various sizes and configurations. The number of tape cartridges that can be loaded into such tape libraries varies depending upon model, but may be on the order of 400-500 tapes, for example.
A typical tape library usually has a control and display panel (or operator control panel) where local functions are controlled and where the health of the tape library may be displayed. The display typically presents information about components in the tape library that are built by the original library manufacturer. Value added components may also be installed in the tape library including software tools to aid in the configuration, installation, and management of the tape library.
Tape libraries inventory the media in the library at power up and are not ready for operation until the inventory is complete. With large libraries, it can take a long time to inventory, which is sometimes inconvenient. The inventory process for a tape library containing 400-500 tapes, for example, can take up to 60 minutes to complete. If restrictions are imposed on the operating modes that can be used by the customer, this may cause customer dissatisfaction and may cause loss of sales if the customer is not willing to accept those requirements.